cocos2d-x v3.2 FlappyBird 各个类对象具体代码分析(4)

今天要讲的使我们猪脚类

SpriteBird.h

SpriteBird.cpp

猪脚类要注意的是三种状态的切换，和单点触控侦听的设置，还有就是小鸟在飞行的过程中，头部会上下的摆动，物理模型这里就不说了，小鸟头部的摆动是靠小鸟Y轴的速度来判定的，当小鸟向上飞的时候，速度是正的，所以头部摆动的旋转角度也是向上，当小鸟下落的时候，速度是负的，所以头部摆动的旋转角度是向下的。

小鸟的三种状态：

下面是代码

//SpriteBird.h
#pragma once
#include "cocos2d.h"
//小鸟的三种状态
typedef enum ActionState
{
	ACTION_STATE_IDLE,					//空闲状态
	ACTION_STATE_FLY,					//飞行状态
	ACTION_STATE_DIE					//死亡状态
};

class SpriteBird:public cocos2d::Layer
{
public:
	SpriteBird();
	~SpriteBird();
	static SpriteBird * createBird();
	//状态转换函数
	void changeState(ActionState);
	//转换成空闲状态
	void stateIdle();
	//转换成飞行状态
	void stateFly();
	//转换成死亡状态
	void stateDie();
	bool init();
	void update(float);
	CREATE_FUNC(SpriteBird);
private:
	//小鸟精灵
	cocos2d::Sprite * sprite_bird;
	//当前状态
	ActionState bird_state;
	//侦听对象
	cocos2d::EventListenerTouchOneByOne * listener;
	

};

//SpriteBird.cpp
#include "SpriteBird.h"
#include "define.h"
USING_NS_CC;
SpriteBird::SpriteBird()
{
}

SpriteBird::~SpriteBird()
{
}

bool SpriteBird::init()
{
	if (!Layer::init())
	{
		return false;
	}
	auto origin=Director::getInstance()->getVisibleOrigin();
	auto visibleSize=Director::getInstance()->getVisibleSize();

	Animate * animate;
	//下面是随即产生三种小鸟（红色，黄色，蓝色），并实例对应的飞行动画
	switch (int temp=int(rand()%3+1))
	{
	case 1:
		{
			sprite_bird=Sprite::createWithSpriteFrameName("bird0_0.png");
			animate=Animate::create(AnimationCache::getInstance()->getAnimation(BIRDANIMATION_0));
			sprite_bird->runAction(RepeatForever::create(animate));
			break;
		};
	case 2:
		{
			sprite_bird=Sprite::createWithSpriteFrameName("bird1_0.png");
			animate=Animate::create(AnimationCache::getInstance()->getAnimation(BIRDANIMATION_1));
			sprite_bird->runAction(RepeatForever::create(animate));
			break;
		};
	case 3:
		{
			sprite_bird=Sprite::createWithSpriteFrameName("bird2_0.png");
			animate=Animate::create(AnimationCache::getInstance()->getAnimation(BIRDANIMATION_2));
			sprite_bird->runAction(RepeatForever::create(animate));
			break;
		};
	default:
		{
			log("bird:%d",temp);
			break;
		}

	}
	//这里是小鸟的物理模型，这里不多讲了，具体看上一章

	PhysicsBody * body=PhysicsBody::create();
	//小鸟的刚体是个圆
	body->addShape(PhysicsShapeCircle::create(BIRD_RADIUS));
	body->setDynamic(true);
	body->setLinearDamping(0.7f);
	body->setGravityEnable(false);
	body->setCategoryBitmask(1);
	body->setCollisionBitmask(-1);
	body->setContactTestBitmask(-1);
	sprite_bird->setPhysicsBody(body);
	sprite_bird->setPosition(Point(origin.x+visibleSize.width/2,origin.y+visibleSize.height*0.6));
	this->addChild(sprite_bird);

	//下面是小鸟的点击侦听，listener是单点触控
	//每次点击小鸟都会向上（Y轴）飞一段距离
	//这里我们就给它赋值一个初速度（Y轴）
	listener=EventListenerTouchOneByOne::create();
	//设置触控是否向下传递
	listener->setSwallowTouches(false);
	//点击开始（单点触控一般分为三种状态，触控开始（onTouchBegan），移动（onTouchMove），触控结束（onTouchEnd））
	//这里只用到了触控开始和结束
	listener->onTouchBegan=[=](Touch * t,Event *e)
	{
		//触控开始时什么都不做
		//注意这里要有返回值（bool）
		log("touch begin");
		return true;
	};
	listener->onTouchEnded=[=](Touch *t,Event *e)
	{
		//触控结束时，播放音效
		CocosDenshion::SimpleAudioEngine::getInstance()->playEffect("sounds/sfx_wing.mp3");
		//给小鸟一个初速度
		sprite_bird->getPhysicsBody()->setVelocity(VELOCITY);
		//注意这边没有返回值
	};
	
	//这里开了个定时器，防止小鸟飞出边界，和小鸟头部旋转角度设置
	this->scheduleUpdate();
	return true;
}
//创造小鸟对象
SpriteBird * SpriteBird::createBird()
{
	SpriteBird * temp=new SpriteBird();
	temp->init();
	return temp;
}
//小鸟三种状态的切换
void SpriteBird::changeState( ActionState as)
{
	switch (as)
	{
	case ACTION_STATE_IDLE:
		stateIdle();
		break;
	case ACTION_STATE_FLY:
		stateFly();
		break;
	case ACTION_STATE_DIE:
		stateDie();
		break;
	default:
		break;
	}
}

//切换到空闲状态
//1:把小鸟添加到点击侦听中去
//2:小鸟移除重力感应（因为在这个状态下，小鸟是悬停在空中的）
void SpriteBird::stateIdle()
{
	_eventDispatcher->addEventListenerWithSceneGraphPriority(listener,sprite_bird);
	sprite_bird->getPhysicsBody()->setGravityEnable(false);
}
//切换到飞行状态
//设置重力感应
void SpriteBird::stateFly()
{
	sprite_bird->getPhysicsBody()->setGravityEnable(true);
}
//切换到死亡状态
void SpriteBird::stateDie()
{
	//播放音效
	CocosDenshion::SimpleAudioEngine::getInstance()->playEffect("sounds/sfx_die.mp3");
	//关闭定时器
	this->unscheduleUpdate();
	//移除点击侦听
	_eventDispatcher->removeEventListener(listener);
	
	//开启重力感应（因为死亡后会自由落体.....）
	sprite_bird->getPhysicsBody()->setGravityEnable(true);
	//停止小鸟的所有动画
	sprite_bird->stopAllActions();
	//设置角度，头向下...
	sprite_bird->setRotation(BIRD_DIE_ROTATION);
}

void SpriteBird::update( float )
{
	auto origin=Director::getInstance()->getVisibleOrigin();
	auto visibleSize=Director::getInstance()->getVisibleSize();
	//防止飞出边界
	if (sprite_bird->getPositionY()>(origin.y+visibleSize.height))
	{
		sprite_bird->setPositionY(origin.y+visibleSize.height);
	}
	//小鸟的飞行头部的角度，根据飞行的Y轴速度决定
	sprite_bird->setRotation(sprite_bird->getPhysicsBody()->getVelocity().y*-0.1);
}